It will not work with the Aero Precision M5 (DPMS pattern)
The ArmaLite AR10 Tactical Handguard Kit is proprietary to Armalite AR10 A and B Series Rifles and uppers only.
From what information I could find the ArmaLite AR10 Tactical Handguard Kit might work with that rifle. However, I recommend contacting Noveske to confirm compatibility.
ArmaLite does not provide the internal dimensions of the AR10 Tactical Handguard Kit. They do state it will require a low profile gas block. I would recommend reaching out to them directly for more information.
https://www.armalite.com/Armalite/Contact-Us
Yes. You would remove the old hand guard and barrel nut.
Difference is mostly aesthetic though it can be affected by barrel length. If you have a 13" barrel and no suppressor, you won't want to use the 15" as the handgaurd will heat up and distort in shape from the muzzle blast. Other than that, the decision comes down to how much of the barrel you want to extend beyond the handguard.
1-7/16” and 18 TPI-3A
No, unfortunately not.
You will not have to change gas block
It should work together.